Peroxidases (EC 1.11.1.X) are the most popular enzymes in analytical chemistry and medical diagnostics. Usually plant peroxidases are used in common practice. The best studied enzyme is the horseradish peroxidase (HRP) C1A. The recovery of peroxidases from plant sources entails some difficulties in enzyme purification because of enzyme content dependency on cultural conditions. These disadvantages led to the necessity to find alternative peroxidase sources. In recent years the progress made by genetic engineering in cloning of eukaryotic genes in heterologous systems open up new opportunities for selection of producers of this enzyme. Now there are several HRP expression systems. Expression in E. coli often serves to obtain recombinant HRP. In this case the enzyme is derived in an insoluble and inactive form. Refolding and reactivation is time-consuming and multi-step process. The secretion of HRP in the periplasm of E. coli cells results in small amounts of active and soluble enzyme. Recently, yeast systems have been engaged to obtain active soluble HRP. The aim of this work was to construct a vector for the expression of the gene encoding HRP C2 in Pichia pastoris cells and to obtain transformants synthesizing this enzyme. The plasmid pPICZαA was used for constructing the expression vector in P. pastoris. The gene HRP C2 was synthesized artificially by Eurofins Scientific Company. The codon optimization for gene expression in P. pastoris was carried out previously. Plasmid pPICZαA-HRP was engineered. The restriction analysis of the plasmid, shown in the figure, was performed using EcoRI restriction enzymes (the size of the DNA fragments after restriction was 3593 bp and 1004 bp), HindIII (plasmid size 4597 bp), and BamHI (3702 bp, 475 bp, 420 bp) and the necessary genetic construction was selected. T hus, the recombinant plasmid DNA pPICZαA-hrpC2 was obtained, and further inserted into the yeast strains - producers of HRP C2. The resulting transformants synthesized hrp in active form.